Updated at 8:34 p.m. ET: Oklahoma firefighters on Monday battled flare-ups and hot spots across the state as medical officials tried to identify a body burned beyond recognition in a rural Norman home.

Crews had battled 18 wildfires that hopscotched across Oklahoma since Friday, torching at least 121 structures and charring almost 94,000 acres amid a drought.

Fires left only ashes in some spots, while property just feet away looked remarkably untouched. In some cases, the flames shifted with the wind, while in others, streams or ponds forced a detour.

Keli Cain, a spokeswoman for the Oklahoma Department of Emergency Management, said all the fires were either under control or in "mop-up" stages early Monday afternoon. Mop-ups could go on for days, Cain said.

Tom Gilbert / AP file

Smoke covers Highway 48 on Saturday, east of Drumright, Okla.

Twelve fires, including "a couple of new ones," continued, Cain said.

"High heat, low humidity and very strong winds make it difficult for crews and easy for fires to spread," Cain said.

One, which threatened the small town of Luther over the weekend, is being investigated as a possible arson. Witnesses told Oklahoma County sheriff's deputies they saw a man throwing a lighted newspaper from a black Ford pickup, but no arrests have been made.